赖氨酸采食量对早期断奶仔猪生长发育及胰腺内分泌机能的影响

将55头21日龄断奶的雄性仔猪随机分为5组，各组仔猪饲喂赖氨酸含量为0．60％、0．80％、1．00％、1．20％和1．40％的试验日粮21d。42日龄结束饲养试验时进行葡萄糖灌注试验，观察赖氨酸采食量对早期断奶仔猪生长发育和胰腺内分泌的影响。结果表明：早期断奶仔猪体增重与赖氨酸采食量为强正相关，根椐体增重指标，21～42日龄阶段，仔猪的赖氨酸采食量不应低于3．16g／d，日粮赖氨酸含量不应低于1.40％。赖氨酸严重缺乏(采食量小于1．45g／d)时，胰岛素的分泌量下降，对高血糖应激的反应能力降低。     

茄子新品种晋紫长茄的选育

晋紫长茄是以临猗紫长茄经多代自交选育的自交系104-126-43-18为母本,以柳林长茄经多代自交选育的自交系237-9-27-11为父本配制而成的一代杂种。植株直立,生长势强,结果能力强;果实长筒形,果皮鲜紫光亮,果肉白色,肉质细嫩松软,口感好,单果质量500g左右;中早熟,从开花到采收15~20d(天),每667m2产量5000kg左右;对黄萎病的抗性强于对照短把黑。适合春夏季露地栽培。     

补播和划破草皮对退化亚高山草甸植被恢复的影响

在甘肃省甘南州临潭县研究围栏内补播和划破草皮对退化亚高山草甸植被的高度、总盖度、地上生物量和功能群物种多样性总指数的影响。结果表明,在各划破草皮处理中,牧草总盖度、地上生物量和功能群物种多样性总指数随着补播量的增加而增加,植被高度随着补播量的增加呈先增加后降低的趋势。补播和划破草皮有显著互作效果,补播量3[垂穗披碱草(Elymus nutans)播量为49.1 kg·hm-2,老芒麦(Elymus sibiricus) 播量为67.5 kg·hm-2,紫花苜蓿甘农1号(Medicago sativa cv.Gannong No.1)播量为23.3 kg·hm-2]和划破草皮组合的牧草地上生物量(201.5 g·m-2)、总盖度(88.2%)和功能群物种多样性总指数(1.203)达到最大值,补播量1（垂穗披碱草播量为26.7 kg·hm-2,老芒麦播量为37.5 kg·hm-2,紫花苜蓿甘农1号为0）和划破草皮组合的植被高度(11.7 cm)达到最大值。就各补播水平平均值而言,划破草皮植被高度、总盖度、地上生物量和功能群物种多样性总指数显著高于未划破草皮。综合考虑高度、总盖度、地上生物量和功能群物种多样性总指数,经关联度分析可知,补播量2（垂穗披碱草播量为37.5 kg·hm-2,老芒麦播量为52.5 kg·hm-2,紫花苜蓿甘农1号18.3 kg·hm-2）和划破草皮为最优组合。     

始丰微型牛体型与外周血cAMP、PTH和TGF-β水平关联性分析

为阐明始丰微型牛的生长发育相关的生化特性,采用ELISA方法对15月龄的始丰微型牛和作对照的正常体型天台黄牛测定并比较分析外周血中三个生长发育相关因子:cAMP、PTH与TGF-β.结果表明:微型牛组TGF-β含量(192.6 ng/L)极显著低于对照组(229.5 ng/L)(P＜0.01),cAMP和PTH含量与对...     

Molecular cloning and functional analysis of duck Toll-like receptor 5

Toll-like receptor 5 (TLR5) is responsible for the recognition of bacterial flagellin in vertebrates. In this study, we cloned the single-exon TLR5 gene of the Maya breed of Common Shelduck (Tadorna tadorna). The TLR5 open reading frame is 2580 bp in length and encodes an 859-amino acid protein. The putative amino acid sequence of duck TLR5 consisted of a signal peptide sequence, 11 leucine-rich repeat domains, a leucine-rich repeat C-terminal domain, a transmembrane domain, and an intracellular Toll-interleukin-1 receptor domain. The duck TLR5 gene was highly expressed in the lung, bone marrow, spleen, and liver; moderately expressed in kidney, small intestine, large intestine, and brain. A plasmid expressing duck TLR5 was constructed and transfected into HEK293T cells, and expression was confirmed by indirect immunofluorescence assay. HEK293T cells transfected with duck TLR5- and NF-κB-luciferase-containing plasmids significantly responded to flagellin from Salmonella typhimurium, indicating that it is a functional TLR5 homolog.     

坝上农牧交错区一年生饲草与主要农作物水分利用效率比较研究

为探究河北坝上地区饲草与作物对水资源的利用程度,本研究在河北省察北管理区种植3种一年生饲草(燕麦Avena sativa L.、箭筈豌豆Vicia sativa L.、玉米Zea mays L.)和4种主要农作物(莜麦Avena chinensis Metzg.、小麦Triticum aestivum L.、胡麻Linum usitatissimum L.、马铃薯Solanum tuberosum L.),通过种植试验比较一年生饲草和农作物水资源利用效率的差异,得出以下结论：一年生饲草产量高于农作物,其平均水分利用率(52.93%)比农作物水分利用率(36.33%)高出16.60%,玉米产量(63.92 t·hm^-2)最高,水分利用率最高(141.80%),马铃薯(19.53%)水分利用率最低;一年生饲草水分利用率由植株磷含量、植株钾含量、温度、细胞间CO₂浓度、鲜干比共同解释;农作物水分利用率由茎叶比、植物氮含量和细胞间CO₂浓度共同解释。     

Screening of cold-resistant seedlings of a Chinese wild grape (Vitis piasezkii Maxim var. pagnucii) native to loess plateau of eastern Gansu province,China, as rootstocks

Seedlings of a Chinese wild grape (Vitis piasezkii Maxim var. pagnucii) native to loess plateau of Eastern Gansu province, China, were evaluated to screen cold-resistant rootstocks in Lanzhou area. After 14-year investigation two selections of LDP-191and LDP-294 were screened as rootstocks for two table grape cultivars, ‘Fujiminori’ and ‘Red Globe’, respectively. The two graft unions demonstrated very high cold-resistance as well as good graft compatibility. Furthermore, they could survive through low temperatures in winter without soil coverage together with good fruit quality of the cultivars grafted.     

羊口疮病毒B2L基因密码子偏好性分析

B2L蛋白是羊口疮病毒(ORFV)的主要囊膜蛋白,为重要保护性抗原之一,可刺激机体产生强烈的抗体反应。本研究对B2L基因运用Visual Gene Developer生物信息学软件,分析其在大肠杆菌、毕赤酵母、昆虫杆状病毒表达系统中的密码子使用偏好性,从而选择一个最适表达系统,以增加B2L蛋白的表达量。分析表明,B2L基因在昆虫杆状病毒表达系统中会得到更好的表达,这为B2L基因表达系统的选择提供了参考。     

中草药防治鸡霉形体病的研究

将自然感染MG的土杂鸡,随机分为7组,1、2、3组分别为病毒I号,按每kg体重0.25ml、0.50ml、1.00ml给药,4、5、6组分别为泰乐星,按每kg体重50mg、100mg、200mg给药,2次/d,连续7d,7组为空白对照。投药后,进行临床症状及气囊病理评分、MG血清抗体检测和疗效试验。结果显示:病毒I号与泰乐星在缓解临床症状、减少气囊炎病变率、降低气囊病变程度和死亡率等方面两者均无显著差异(P>0.05),而试验组与对照组差异显著(P<0.05)。说明病毒I号与泰乐星达到同样的治疗效果。     

β-carotene attenuates weaning-induced apoptosis via inhibition of PERK-CHOP and IRE1-JNK/p38 MAPK signalling pathways in piglet jejunum

Weaning may cause oxidative injury, immune response impairment, apoptosis and other injuries in piglets. Oxidative and endoplasmic reticulum stress (ERS) can elicit inflammatory responses, and persistent oxidative and ERS also may lead to apoptotic cascades, which is associated with the pathogenesis of multiple diseases. β-carotene, a natural carotenoid, has potential anti-inflammatory and antioxidant functions. However, the effect of β-carotene on apoptosis in weaned piglets and the detailed molecular mechanism remain unclear. In this study, we found that β-carotene decreased malondialdehyde (MDA) levels and increased the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in piglet serum. β-carotene could inhibit the mRNA levels of caspase-3 significantly, but had no significant inhibitory effect of the mRNA levels of caspase-9 and caspase-12 in the piglet jejunum. In addition, β-carotene decreased the activation of GRP78, CHOP, and JNK/p38 MAPK and the ratio of Bax/Bcl-2. Furthermore, β-carotene had a significant influence on the activation of ERS and apoptosis-related signals in TG-induced IPEC-J2. In the present study, β-carotene pre-treatment attenuated the ratio of Bax/Bcl-2 and prevented TG-induced increases in the level of PERK-CHOP and IRE1-JNK/p38 MAPK pathway activation in a dose-dependent manner. Overall, these findings indicate that β-carotene may protect weaning-induced apoptosis through inhibiting ERS.